Cross-test level and rule



Jan. 9, 1923. 1,441,350

C. HERRMAN. CRoss TEST LEVEL AND RULE.

FILED MAR. 1 9. 1919 2 EEEE TSSHEET I Jan. 9, 1923. 1,441,350

C. HERRMAN. CRoss TEsT LEVEL AND RULE.

FILED MAR. 19. 1919. 2 SVHEETS'SHEET 2 SALE 2"m 1" 33mm (71a: Zes Mama);

Patented den. 9, i923.

CHARLES nnnnianimor NEW YonK, N. Y.

cnoss-rnscr LEVEL Ann RULE. 5

Application filed March 19,'1919. Serial No! 283,447.

'10 vention, such as'will enable others skilled in the art to which it appertains to make and use the same. V

This invention relates to instruments of precision and more particularly it pertains to levelling instruments. 5

Spirit levels comprise, the combination, usually, of a suitable straight-edged or plane surfaced element on or in which there is embodied a spirit glass or vial, a sufficient quantity ofthe spirit being put in the vial to leave an air bubble. Hence, as is well known, gravity acts on the spirit so that the air bubble always seeks the highest point in the vial, and therefore when the instrument is applied to a plane surface the bubble serves to indicate level. When the spirit glasses or vials are. longitudinally curved, for accuracy the convex surface of. the curved vialmust be made the highest point in all directions of the instrument, transversely as well'as longitudinally. In the finer class of levelling instrumentstwo separate spirit glasses or vials are combined in the one instrument on lines substantially at right angles to each other for the purpose of providing a cross-test, thereby indicating that the plane on which the instrument may I be supported is level in more than one direc tion horizontally. Obviously, those types of spirit levels in which the longitudinally curved vial is employed may give an erroneous indication when the levelling in strument is canted or tilted transversely with the resultant efl'ect of causing the bubble, which should be at the highest point when the instrument is level, to shift. And, equally, it is essential .in the making of a. v leveling instrument that the spirit glass. or vial be associated or incorporated with very careful regard both as to its horizontal and angular relation to the'base surface to get exact accurate reading for level. It is therefore one of the objects of the present invention to provide asi m'ple, practicable, durable and inexpensive instrument for accurately indicating that a surface or plane is level in one or more directions horizontally-by a single setting of the instrument and without requiring any further movement or adjustment by affording simultaneouslya cross-test indication 'as for instance of the level both longitudinally and transversely of the surface being tested. Another object of the present invention is to provide a cross-test levelling instrument capable of being collapsed or folded into a compact position of parts and which may,

by its. inherent construction, serve as, and. has the further ob]ect of providing, a means for double checking in the levelling of the lnstrument by the cooperation of dual spirit vials or levels which may be arranged laterally in parallelism side by side or which may be arranged in co-axial positions. In other words, it is the object of the invention to provide a "double vial spirit level for checking the individual glasses one against the other in lateral relation and to provide a level instrument having a maximum area broad base to assure accuracy and further to provide a levelling instrument extensible in length and having dual interchecking spirit levels 5 Further objects ofthefinvention are, to

provide a leveling device which is extremely compact in construction and which has its several faces free from undesirable protuberanceswhich, when present, naturally interfere with various uses to which the instrument may be applied as well, also, male ing it inconvenient to handle; and to provide' a structure giving maximumbearing area of baseplane by utilizing the width dimension, of the beam, instead of the edge dimensions asvthe basesurface. A further objectlis to provide an improved level and rule combination conforming, as nearly as possible, to standard, present construction of 4-section, 2-foot rules. i

Another object of'the present invention is to provide a combinedspirit level and folding rule of a'plurality of sections in which certain of the sections have wholly embodied therein the spirit level means, thus protecting the level glasses or vials against injury and also forming substantially unobstructed, smooth and plain, foldably connected sections and elements so that the combination manner, spirit glasses or vials, the sections bong so proportioned and gt'oldably connected and related that while certain of the sections may he thicker than other elements, yet the several foldable members n a-y be extended in a continuous line to seem-e the in: vim um length of measuring function and also present one continuous and uninterrupted, smooth face the length of the rule.

Another object of the invention is to present and retain, at the sides of the instru ment two straight line, unbroken and uninterrupted edges as for inez suring ruling and observation, by placing of the spirit vial in longitudinal i'ne somewhat medial to the rules width. I

Another obj eet of the invention is to provide for the effectual protection oi" the embedded spirit vials org-Lasses in their respective positions in the level sections or elements; and further, to provide for the utilization ojt' (the pnotectingr means ol the it glasses as component elements of the b aduated rule faces so that the combination of the protecting means does not intertere with'the continuity of the grednations of the respective faces of the nu e.

With these and other objects in view, as will be rendered manifiestto those versed in the art, the invention consists in the construction, the combination and details and elements of the parts as more particularly described in the following; specification relative to the accompanying drawings in which:

Figure 1 illustratesthe improved level as japplied for indicating the levelof a plane in two directions at right angles to each other. a

Figure 2 shows the instrument in fully extended position so that the dualspiri-t glassesuare utilized to check each other in indicating the level of a plane in one direction.

igure is a perspective view of the completely folded 2111601 collapsible levelshowingflthe end elements overlapping the .in termediate sections and indica ing how the subjacent level glasses can be observed through the overlaid stop elements without requ ring the unfolding oi the sections.

F gure 4 an end elevationon an. en-

larged scale, of a portion of the instrument shewingelearly the form of the hinge ijoint onn c ing h and elemen s tothe inte m die seetionsi ,Fig e s rlQl gllllldwel, verticalv section through a fragment of a rule section indicating the method of mounting the spirit glass or vial.

Figure 6 is a cross section on line 6--6 of Fig. 5.

Figure 7 is a. perspective view of the cross-test level with the intermediate sections adjusted at right angles and with the outer end elements overlapping the top faces of the sections.

lVhile I have shown my improved level as embodied incombination with a standard and well-known .fol-ding rule of the foursectiontype, it is obvious "that it may he used in .a. combination o'l elements ent 'e-ly without any surface indieiaor with any suitable surface indicia and also that it may be utilized in elements suitably connected and related to permit i the designated adjustment of the parts one to the other and lurthermore it is to be understood that this may be embodied in a folding structure constructed of any suitable material.

I haveshown the instrument ascomprising rule having intermediate sections 2=-2 of suitable width thickness and length and which are connected to move in a common plane edgewise about apivotal connection or joint 3 oi the well-known ruler butt joint type solhat faces 4+4 vof the rule or tolding ,elen'ients may be brought intov edgewise iiugtapositions as when the instrument is collapsed (Fig. v3) or maybe moved out.- vardly aboutqthe pivot 3 to the position shown in Fig. 2 and the edges brought into alinement; Hingedly connected to the swinging ends of the sections 22 as by hinges 5v5 are end elements or end sections -G6 which if desired may be and preferably are, provided with end wear plates 7 of the usual well-known form. The of thehine'es are, as shown, set transversely (to the ,lengthzof the sections and Lelenirentstj so that these may be swung into longitudinal, overlapping positions. The faceiof the ruleshown in Figs. 1 and 2 is provided with any suitable graduation lines or indicis, indicated at G, ambit desired, the edges 4; of nil iolding members of the level or ruleni' elled, as portion to inore ents made ale upper e readable level. i line or lines indi tine ble in the spirit vial at y of ineasu euations G on d a position by level .coincl .a graduation mark .or with graduation marks on the bevel face. v

lhave provided the combination with suitable folding members of 21 dual. set of horizontal; indicat 1g means which. are, as here shown, inthe fornrof. the well-known spirit level 251 2 5 character,indicated at '10, 5. audit; th sevg a s s or v als-being,

preferably, respectively wholly embedded in may be indicated.

sections on opposite sidesof the hinge on joint 3, preferably insections 2 and are fixedly secured, as by cement, which is indicated at 11, or otherwise. U Spirit level glasses or vials are of various types, and proportions and d ameters and I have preferred to show the type of glass or vial which is longitudinally curved or which has a convex Surface thereby increasing the accuracy and facility with which level observ'ationT prefer toapply to the top surface of the folding sections protecting or guarding plates 13, which preferably extend from edge to edge of the'intermediate section o'n which they maybe mounted, and when these top facesare bevelleddown, as at 1 3*, to conform. to the bevel of the face.

From the above it will be seen that there are no projecting parts on the surfaces ofthe sections. The guard plateiss'hown asprovided with an oval or longitudinal aperture or window 14;, extending just above the crest of the vial 10, so that the bubble maybe readily seen. The level is constructed in organization with elements having face indicial or graduations, G, and I prefer that the guard plates 13be exactly of a length equal to one or more of the unit graduations; in

this 'case each plate being two incheslong, so that it may have its central portion provided with an index line coordinate with the respective scale unit line at the point centrally between the .ends, of the guard plate. Thisindex line'15 also coincides with an index mark or line 16 at the crest of central portion of the level glass or vial. While the foregoing describes the preferred ems.

bodiment of the invention, obviously,,con.-,

siderable modification may be had without departing from the spiritand scope of the invention.

In the preferred embodiment the. inter mediate sections 2 of the foldinginstrument as somewhat thicker (say 1 g) than the end elements 6 (say :1- thick) see illustrated enlarged in Fig. 4;, and for the purpose of enabling all of the sections and elements to be fully extended in alinement and atthe same time present one continuous; smooth and plane bottom or base 3, I have utilized a peculiar form of hinge 5 connecting adja-- cent ends of one section 2 and an endele mentfi. This hinge is formedof usual hub portions which. are arranged along an axis or pivot shaft 20 which is shown as disposed in the medial plane between the upper surface atB in Figure 3 and the base surface B of the folded elements so that when the element or elements 6 are outwardly folded In the preferred illus-v trated embodiment of the invention, the vials 10 are completely 'setin pockets 12; and cementedas at 11, and to protect the same against injury'and also'to facilitate accurate B of the intermediate sections 2. a y a V The end elements 6-6,' whenfoldedover,

serve to guard the level vials and they-are prov ded, with windows or apertures 22 dis .posedto be brought into pixtaposition with the leveljvials or glassesflO when theend elementsfi arefolgled over as shownin Fig. 3, so that the instrument may beutilize'd as I vthe surface B?thereofawill come into the v plane. of'the surface a level ;without requiring the opening of thej top sections in the position shown in Fig. 1

the; vials being readily observedby looking.

downwardly-as indicated by the arrows in Frointhe above, it will be seen that I have provided a compact 'foldable or colobservation and deduction of level in. two

directions horizontally; from 0:to 180 and particularly as shown 1 in Figs. 1 and Tat instrument, thus obviating the changingof position of theinstrument to determine level in more thanone direction; and also, I have provided a level-. having a double checking feature, which is the result of providing two. fol dably connected plane sections "or membersas parts 2+2 which when brought into. parallelism; (Fig. 3) check the vials against each other in their indication; and.

alsodouble the efiiciency of the device'by virtue of the increase in the width of the v base B of the level Further the instrument 'alapsible pocket spirit level which enables the .90", or what isknown as cross-test leveling .at a s multaneous reading andsetting of the is serviceable as' checkingiin observations by f reason of the capacity foreXtension' of the level SGClllOIlS2-2 into alinement with one another as shown in Fig. 2 so as to further increase the ,accura'cyof the reading by having the double levels presented in alinement when taking a level in one direction. i a

What Iclaim is: 1 I

1. Acombined folding rule and leveling instrument,comprising a section having an 7 1 hinge being so disp'osedthat the second section may foldover the vial on, the firstsection or extend in alinement with said first section so that their under basesurfaces are then co-planar. 1

2. A combined folding rule level, comprising foul-sections of greater width than thickness hinged end toend so as to "fold in parallel'relation to each other, or to. open in alinement with their base surfaces in a commonplane, the intermediate andcross-test tally-and angularly disp osed \vith respect to sections being hingedtogether so to open and close edgewise' with "respect to each other, and the other sectionshei-ng hinged to fold fletwise ugonthe intermediate sections; and two level-indicatingfviais mounted respectively, in eetions on opposite sides of the hinge connecting the intermediate sections, each vial being similarly horizonthe base surface of the sec tionon which it is mounted so as to, indicate level when said hose surfaces are horizontal.

A combined folding rule end le'reling instrument conihrisiiw intermediate sections pivoted together so that their under base surfaces are constrained to oeeupy 00111111031 plane in all relative positiongemh of said upper readingfaees of theintermediote sections over the vials.

4-. A combined iiioldil'zg f rule and level comprising ztsectio n having a level indicating vial imbedded below a surface thereof and visible therethrough; a second section pivoted'to said first mentioned section so as to foldvnpon said surface over said vial, and

means whereby said viiil is rendered Visible through said second section when the latter is folded over it. v

F5.- A 'le'veiiing instrument comprising a p cur oi'intermediate sections pivoted at one endto each otherto" swing' edgewise, outer or end elements hinged to the 'swin ing "ends of the intermediate Sections to fold over the :tuee of the same; and levelhng means sunk in the "feces of the said sections; the other elements having- Windows through which the said means ma'y"be' observed.

in testimony whereof I 21th:; mysignature.

CHARLES HERRMAN. 

